Conventional perfuming compositions have a fragrance profile characterized by the classical fragrance pyramid three-tiered structure, which contains a higher amount of the base notes, a medium amount of the heart notes, and a lower amount of the top notes (see FIG. 1a). The conventional pyramid structure is used because higher levels of the base notes are relied upon to provide the intensity of the overall fragrance profile over time and replace the heart notes when those are declining. Simply increasing the levels of heart and top notes does not provide the required longevity because of their fast evaporation.
Perfumers typically classify fragrance materials as a base, heart or top note according to their specific characters. For instance, the fragrance material “Hedione®” (or also known as “methyl dihydrojasmonate”) is commonly classified as a heart note based on its perceived floral character. However, due to the somewhat subjective nature of characters, there has been no universal convention for objectively classifying fragrance materials. As a result of the subjective classification approach, fragrance formulation has been inconsistent. For example, two compositions having the exact same classification of fragrance materials constructed according to the classical fragrance pyramid structure could have two different, possibly very different, fragrance profiles.
With the classical fragrance pyramid structure, “base notes” make up from greater than 30 wt %, typically greater than 40 wt % or typically greater than 50 wt %, relative to the total weight of the perfume formulation. Base notes are characterized by providing animalic, woody, sweet, amber or musky characters, and not being very volatile. The “heart or middle notes”, make up from about 0.1 wt % to about 60 wt % relative to the total weight of the perfume formulation and have an intermediate volatility. Heart notes are associated with desirable characters such as floral characters (e.g., jasmin, rose), fruity, marine, aromatic or spicy characters. The “top or head notes” provide citrusy, green, light, or fresh characters, and make up from about 0.1 wt % to about 40 wt % relative to the total weight of the perfume formulation. Top notes tend to evaporate quickly due to their high volatility.
There are at least one of several drawbacks to the above described classical formulation approach. Firstly, classification of fragrance materials by their characters is subjective and therefore results in inconsistency in the fragrance profile under classical fragrance pyramid construction rules. Secondly, the perceived intensity of the fragrance profile of the conventional perfume compositions, particularly those characters attributable to the more volatile fragrance materials, decreases rapidly over time due to their quick evaporation. Accordingly, conventional perfume compositions will typically change their overall fragrance profile over time. This is a problem because it is desirable to maintain “fragrance profile fidelity” over time. In other words, it is desirable to maintain the same or substantively similar fragrance profile for a commercial fragrance over time, particularly over long periods of time (at least 4 hrs, 6 hrs, or even 8 hours after application). Thirdly, with the classical fragrance pyramid construction, the possible types of fragrance profiles have been somewhat limited. The consequence of using base notes at high levels is that many fragrance dry-downs appear repetitive, boring, non-memorable and un-interesting to consumers. However, if base notes are reduced or excluded then the fragrance intensity weakens over time and does not last for a sufficient duration. Lastly, it is generally accepted that some consumers desire prolonged intensity of select characters, particularly the floral, spicy or aromatic characters derived from the heart notes. Unfortunately, the consequence of using high levels of base notes is that they may impart particularly undesirable characters, such as for example, musky, woody, ambery, warm and sweet, which overpower and dominate the more desirable fragrance characters over time, particular over long periods of time. Thus, the unique challenge remains of selectively extending the more desirable characters attributable from the heart and/or top notes, particularly the heart notes, and even more particularly extending these desirable characters over long periods of time.
Previous attempts to overcome these problems have been through the use of various “fixatives” or “modulators” to retard the evaporation of the more volatile fragrance ingredients present in fragrance compositions. For instance, U.S. Pat. No. 6,737,396B2 (Firmenich) describes a perfume composition formed by mixing 2-30%, relative to the weight of the composition, of a fixative, (1-ethoxyethoxy)cyclododecane, to fix or exalt the musky or aromatic-type notes. U.S. Pat. No. 6,440,400B1 (Takasago Perfumery) describes a composition using trimethylcyclohexane derivatives as perfuming-holding agents and melanin-formation inhibitors. U.S. Pat. No. 4,313,855 (Dragoco) describes the use in cosmetic compositions of 1-(2,6,6-trimethylcyclohexyl)-hexane-3-ol as an odourless fixative for increasing the perfume's intensity. U.S. Pat. No. 6,147,049 (Givaudan) discloses a perfume fixative derived from tera-hydronaphthalenese for use in a wide range of fragrance compositions. WO85/04803 (Diagnostica) describes the use of hyaluronic acid/hyaluronate as fixatives (via molecular encapsulation) in fragrance products to improve persistent of the fragrance. JP Patent No. 61-083114 (Kanebo) describes ether derivatives as aroma-preserving agent for fine perfume composition. JP Patent No. 61-063612 (Kanebo) discloses diethylene glycol ether derivatives as fragrance adjusting agent showing effects as a fixative and a solubilizer. JP Patent No. 62-084010 (Shiseido) describes hydroquinone glycoside as perfume fixatives applicable for all kinds of perfume and blended perfume. U.S. Pat. No. 7,196,052 (Takasago Int. Corp.) describes fragrance compositions containing glycerol ether derivatives as fixatives or fragrance note-improving agent. EP Patent Publication No. 616800A2 (Givaudan) discloses odourant compositions containing panethenol ethyl ether having improved prolonged diffusion of the perfume materials from the skin, without notably modifying the olfactive note of the product. U.S. Pat. No. 4,110,626 (Shiseido) describes the use of aliphatic dibasic acid diester as “perfume controlling agent” for improved fixing effect on fragrance component. PCT Publication No. WO2014/155019 (LVMH) describes aliphatic ether derivatives to increase the stability of alcoholic fragrance composition and more particularly to preserve the original olfactive notes.
These attempts have advocated the use of such fixatives or modulators indiscriminately without regard to the fragrance profile. Further, these attempts do not teach how to objectively classify the fragrance materials as low, moderate or high volatile fragrance materials. Further, the use of fixatives or modulators in these attempts often shows effects on single fragrance material, which are often not observed in a fragrance composition of a mixture of fragrance materials where a number of such fragrance materials are competing with each other to interact with said fixatives or modulators. They do not teach how to formulate with fixatives or modulators in fragrance mixtures, which is not trivial. As a result, these attempts, while disclosing compositions that retain the perfume by way of fixatives or modulators, neither teach the fragrance diamond construction in compositions nor the particular type or levels of fragrance materials to include for delivering the benefits of improved fidelity to the perceived fragrance profile over time, or improved longevity of the fragrance profile, preferably the characters attributable from the moderate or high volatile fragrance materials, particularly the moderate volatile fragrance materials.
On the other hand, other attempts propose a selective approach aimed at the selection of specific fixatives or modulators and defined amounts of fragrance materials. For instance, U.S. Pat. No. 7,538,081 (Takasago Perfumery) approaches the problem of fixing a perfume and/or extending the perfume release from a fragrance composition. More particularly, said document describes the use of L-menthoxy ether derivatives as fixatives in fragrance compositions comprising at least one note selected from: floral, citrus, fruity, green, mint, herb and marine. U.S. Patent Publication No. 2011/0104089A1 (Symrise) describes certain compositions containing neopentyl glycol diisononanoate as a fixative for top note perfume oils by increasing their adhereance to skin and hair. U.S. Patent Publication No. 2011/0091404 (Symrise) discloses the use of N-hexadecyl n-nonanoate and N-octadecyl n-nonanoate as fixatives of fragrance substances, particularly the readily volatile top notes, by lowering their vapor pressure to allow for a time-delayed release of the perfume oil components from a composition.
However, these attempts tend not to describe how to formulate with fixatives or modulators in complex mixtures of fragrance materials. For those references that do describe mixtures of fragrance materials, they have different fragrance design criteria and are directed to specific preferred fixatives or modulators.